Abstract

Plasmon-active silver nanoparticle layers were included in solution-processed bulk-heterojunction solar cells. Nanoparticle layers were fabricated using vapor-phase deposition on indium tin oxide electrodes. Owing to the increase in optical electrical field inside the photoactive layer, the inclusion of such particle films lead to increased optical absorption and consequently increased photoconversion at solar-conversion relevant wavelengths. The resulting solar energy conversion efficiency for a bulk heterojunctionphotovoltaic device of poly(3-hexylthiophene)/[6,6]-phenyl butyric acid methyl ester was found to increase from to for devices employing thin plasmon-active layers. Based on six measurements, the improvement factor of 1.7 was demonstrated to be statistically significant.

Received 24 October 2007Accepted 19 November 2007Published online 03 January 2008

Acknowledgments:

One of the authors, Anthony Morfa, acknowledges support from an NSF—IGERT fellowship. Financial support was also obtained from Airforce MURI Grant No. 153-6087. This work has been authored by an employee of the Midwest Research Institute under Contract No. DE-AC36-99GO10337 with the U.S. Department of Energy.